The present invention relates to an information transmission system having particular, but not exclusive, application to a multiple user radio system comprising a primary station and a number of secondary stations. The present invention also relates to a primary station and secondary station for use with such a system, and to a method of transmitting information in a multiple user system.
Information transmission systems, for example radio systems, comprising a primary station and a number of secondary stations are often not required to carry information between the primary station and all of the secondary stations for all of the time that the system is operational. Individual secondary stations may only be sending or receiving information for a small proportion of the time. In such situations it is common to want to reduce the amount of attention which the secondary stations pay to the transmissions of the primary station, for example so that a portable radio receiver may reduce power consumption and hence extend battery life.
It is an aim of the present invention to provide a system for, and a method of the transmission of information.